Anabolic-androgenic steroids (AAS) and testosterone are classified as prescription drugs permitted only for the treatment of diseases confirmed by the drug authorities. These diseases include, among others, Testosterone Deficiency Syndrome (TDS) caused by the pituitary gland or testicles, different kinds of anemia, osteoporosis, and chronic diseases of protein deficiency and prolonged tissue healing. Testosterone is also used for treatment of male menopause symptoms.
Testosterone is administered by syringes containing different kind of testosterone esters (for example, testosterone propionate, testosterone enanthate, testosterone phenylpropionate, testosterone isocaproate, testosterone decanoate, testosterone undecanoate) or by mouth using testosterone undecanoate capsules. Anabolic steroids are available both as injections and capsules.
Both AAS and testosterone are doping substances according to the Decree 705/2002 that defines the doping substances that are to be regarded as doping substances referred to in Chapter 44, §16, Subsection 1 of the Penal Code.
The most important reason for using testosterone and anabolic steroids is to increase the muscle mass. On the other hand, by using steroids, people also try to improve their own status in strength sports, for example.
Periodic use is characteristic in the abuse of anabolic steroids. The periods of abuse often last from a couple of weeks to several months. Between them, there are pauses for a couple of months. The dose is increased gradually and the use is discontinued in stages over a 1-2 week period. Excessive doses are often used [1, 2, 3].
Adverse effects: hormonal disturbances
When excessive levels of testosterone and anabolic steroids are introduced to the body, they cause hormonal disturbances.
In men, this suppresses endogenous hormone production. There is structural shrinking in hormone producing glands and organs, such as testicles.The periods of abuse are followed by infertility and weakened sexual functions. [4, 5]
In female users, testosterone and anabolic steroids cause excessive growth of body hair, lowering of the voice, reduction in breast size, balding, enlargement of the clitoris, skin problems and menstrual cycle disturbances. Some of these changes may be permanent. 
In adolescents, growth may stop, leading to short stature .
Adverse effects: severe diseases
When used in excessive doses, both testosterone and anabolic steroids cause harmful changes in cholesterol levels.Thus the continuous use of these hormones will increase the risk of developing heart and vascular diseases, heart infarct and apoplexy. Steroids weaken the cardiac contractile force and cause cardiac muscle degeneration, which can lead to cardiac arrhythmia and sudden death [6, 7, 8].
Abuse of AAS and testosterone increases the risk of diabetes. The sharing of syringes with other users increases the possibility of getting blood-transmitted diseases such as hepatitis and HIV.
Excessive use of testosterone and anabolic steroids also increases the risk of cancer and liver damage [1, 9]. Anabolic steroids that are administered orally are more harmful to the liver than injected anabolic steroids. Liver diseases vary from reversible, slight cell damage and yellowness to malignant liver tumors with a bad prognosis even when treated.
Adverse effects: mental disorders
Testosterone and anabolic steroids also affect the central nervous system. The locations in the brain where they have effects are closely connected to the centers that adjust mood, sexuality and aggressiveness .
About 20 to 30 percent of the people who use excessive doses of testosterone and anabolic steroids have obvious mood disorders that meet the criteria of psychiatric disease classification, such as depression, anxiety, psychotic reactions with hallucinations, and decrease in cognitive performance levels [2, 4, 6].
About 30 percent of the people who use excessive doses of testosterone and anabolic steroids are aggressive, hostile and irritated during the intake period. Based on several case reports, hormones weaken impulse control . These include reports of previously stable individuals becoming violent following hormone consumption.
According to a Finnish population-based study , the risk of anabolic steroid and testosterone abusers dying prematurely was 4.6 times higher than in the control group.
The Finnish Antidoping Agency FINADA
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